Ozone is useful for numerous applications that require a high level of oxidation. For example, ozone is useful for disinfection of drinking water and has been used for water treatment since the early 1900s. More recently, ozone has been used for semiconductor device processing. One application for ozone in semiconductor device processing is forming insulating layers on semiconductor wafers by growing insulating films or by oxidizing thin films on the wafer. For example, high deposition rate chemical vapor deposition of high quality SiO2 can be accomplished by using a TEOS/ozone process.
Another application for ozone in semiconductor device processing is for cleaning semiconductor wafers and the processing chambers of semiconductor processing equipment. Ozone is particularly useful for removing hydrocarbons from the surface of semiconductor wafers or from processing chambers. Using ozone for cleaning is advantageous because it avoids the use of dangerous chemicals which require costly disposal. In contrast, ozone does not present a toxic waste disposal problem because ozone decays to oxygen without residues.